JP2016008925A - Vehicle speed command production system and vehicle speed command production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle speed command production system and a vehicle speed command production method that produce a vehicle speed command which makes driving in a smooth mode, which is closer to driving by a human being, feasible.SOLUTION: A vehicle speed command production system includes extreme value search means that determines a value of an acceleration meeting a condition that a value of an evaluation function having a term proportional to a square of the acceleration of a vehicle becomes an extreme value, and vehicle speed command production means that produces a vehicle speed command using the determined value of the acceleration. The extreme value search means determines the value of the acceleration so that the value of the speed of the vehicle falls within a permissible range determined in response to a predetermined reference vehicle speed command and the value of the evaluation function becomes the extreme value.

Description

  The present invention relates to a vehicle speed command generation device, a vehicle speed command generation method, and a vehicle test system. More specifically, the present invention relates to a vehicle speed command generation device and a vehicle speed command generation method for generating a vehicle speed command used as an input to a vehicle speed control device of a drive robot.

  Vehicle tests such as an endurance test, an exhaust purification performance evaluation test, and a fuel consumption measurement test are performed by actually running an actual vehicle on a roller of a chassis dynamometer, for example. At this time, the driving of the actual vehicle is often performed by an automatic driving device (a so-called drive robot). When a vehicle speed command corresponding to the speed of the vehicle to be realized is input, the drive robot drives the actuator to realize the vehicle speed command, and operates the accelerator pedal, the brake pedal, the shift lever, and the like of the vehicle. Driving the vehicle in accordance with a predetermined vehicle speed command is referred to as mode driving.

  In the vehicle test, the durability performance, the exhaust purification performance, the fuel consumption, and the like of the vehicle are evaluated as a result of the mode operation performed by the drive robot in place of the person. Therefore, the drive robot used for such a test is required to be able to operate a vehicle closer to a person in addition to being faithful to the vehicle speed command. Patent Document 1 discloses a vehicle speed control method using a drive robot for the purpose of realizing the operation of a vehicle close to a person.

  In the control method of Patent Literature 1, a predetermined average vehicle speed command is subjected to a moving average process over a predetermined advance time, and further subjected to a predetermined delay process is input to a driving force characteristic map. An accelerator opening command that is an input to the accelerator actuator is determined. Further, in the control method of Patent Document 1, as a result of the mode operation by the drive robot, the speed of the actual vehicle changes from the reference vehicle speed command to a predetermined allowable range (for example, ± 2 [ km / h] / 1 [s], the advance time is shortened.

JP 2009-8517 A

  According to the control method of Patent Document 1 described above, the moving average process is performed over the advance time for the reference vehicle speed command, and further, the advance time is further varied, thereby realizing smoother vehicle operation closer to humans. It is possible to achieve both mode operation faithful to the reference vehicle speed command as much as possible. According to the control method of Patent Document 1, although a smooth vehicle operation closer to a person is realized as compared with a case where the reference vehicle speed command is input as it is, there is still a somewhat unnatural fluttering in the operation of the accelerator pedal and the brake pedal. It may remain (specifically, refer to FIG. 4 described later).

  The present invention has been made in view of the above problems, and provides a vehicle speed command generation device and a vehicle speed command generation method for generating a vehicle speed command that enables smooth mode operation closer to humans. For the purpose.

  (1) A vehicle speed control device (for example, a vehicle speed control device 2 described later) of a drive robot receives a vehicle speed command (for example, a target vehicle speed command vcmd described later) corresponding to the vehicle speed to be realized. The vehicle is operated according to A vehicle speed command generation device (for example, a vehicle speed command generation device 1 described later) according to the present invention generates a vehicle speed command used in the vehicle speed control device, and is an acceleration of the vehicle (for example, an acceleration a described later). Extreme value search means (for example, an extreme value search unit 12 to be described later) for determining an acceleration value such that the value of an evaluation function (for example, an evaluation function J to be described later) that includes a term proportional to the square of Vehicle speed command generation means (for example, a vehicle speed command generation unit 11 described later) that generates a vehicle speed command (for example, a target vehicle speed command vcmd described later) using the determined acceleration value. The extreme value search means is an allowable range in which the value of the vehicle speed is determined with respect to a predetermined reference vehicle speed command (for example, a reference vehicle speed command vref described later) (for example, an allowable speed upper limit Tupper described later and an allowable speed lower limit). The acceleration value is determined so that it falls within the range of Tlower and the value of the evaluation function becomes an extreme value.

(2) In this case, it is preferable that the evaluation function includes a power term (for example, a power term W ² described later) proportional to the product of the square of the acceleration and the square of the velocity.

  (3) In this case, the evaluation function increases as the speed value approaches the speed upper limit value from within the allowable range, and increases as the speed value approaches the speed lower limit value from within the allowable range. It is preferable to further include a function term (for example, a velocity barrier function term B described later).

  (4) In this case, the extreme value search means, based on the current value of the acceleration, the predicted value of the speed after a predetermined look-ahead time (for example, ndt described later) (for example, the value of the predicted speed vest described later). And the evaluation function increases as the predicted value of the speed approaches the upper speed limit value from within the allowable range after the pre-reading time, and the predicted value of the speed falls within the allowable range after the pre-reading time. It is preferable to further include a prefetch barrier function term (for example, a prefetch barrier function term Best described later) that increases as the speed lower limit value is approached.

  (5) In this case, the extreme value search means uses a transient characteristic model (for example, a transfer function G described later) simulating the transient characteristic from the vehicle speed command to the drive robot to the speed detection of the vehicle. It is preferable to search for an extreme value of the evaluation function using an output obtained by inputting a vehicle speed command generated by the vehicle speed command generating means as a characteristic model as a speed value of the vehicle.

  (6) A vehicle speed command generation method according to the present invention is a vehicle speed command generation method for generating a vehicle speed command used in a vehicle speed control device of a drive robot, and includes an evaluation function including a term proportional to the square of the acceleration of the vehicle. An extremum searching step for determining an acceleration value such that the value becomes an extremum; and a vehicle speed command generating step for generating a vehicle speed command using the determined acceleration value. In the extreme value search step, the acceleration value is determined so that the speed value of the vehicle falls within an allowable range determined for a predetermined reference vehicle speed command and the value of the evaluation function becomes an extreme value.

  (1) In the present invention, an evaluation function including a term proportional to the square of the acceleration of the vehicle is defined, the value of the vehicle speed is within an allowable range determined for a predetermined reference vehicle speed command, and the evaluation function The acceleration value is determined so that the value becomes an extreme value (a minimum value if the evaluation function is positive, and a maximum value if the evaluation function is negative), and a vehicle speed command is generated using the acceleration value. Thus, the vehicle speed command is generated so as to be within an allowable range with respect to the reference vehicle speed command while minimizing a physical quantity proportional to the acceleration (more specifically, for example, power). In other words, when the vehicle speed command generated as described above is input to the drive robot, smooth vehicle operation using the allowable range is realized.

  (2) In the present invention, a function including a power term proportional to the product of the square of acceleration and the square of velocity is used as the evaluation function. As a result, a vehicle speed command can be generated that realizes a smooth vehicle operation that reduces the work rate as much as possible.

  (3) In the present invention, a function including a term proportional to the square of acceleration and a velocity barrier function term that increases as the velocity value approaches the velocity upper limit value or velocity lower limit value from within the allowable range is used as the evaluation function. . Thus, by using the evaluation function in which the speed barrier function term for realizing the above-described constraint condition (the vehicle speed value falls within the allowable range) is used, the extreme value search means can The vehicle speed command as described above can be generated simply by searching for the extreme value of the evaluation function according to a predetermined algorithm without explicitly handling the conditions. Further, for example, when the allowable range is changed according to the test purpose, it is only necessary to change the velocity barrier function term accordingly. Therefore, it is possible to easily generate a vehicle speed command that matches the purpose of the test.

  (4) In the present invention, a predicted value of speed after a predetermined look-ahead time is calculated based on the current value of acceleration. In the present invention, a function including a term proportional to the square of acceleration and a prefetch barrier function term that increases as the predicted speed value approaches the upper speed limit value or the lower speed limit value at that time from within the allowable range after the prefetch time. Is used as an evaluation function. In the present invention, by imposing a constraint condition on the predicted value of the speed after the look-ahead time in this way, for example, in the case where the reference vehicle speed command and the allowable range determined in accordance with this change rapidly, the acceleration is increased. It is possible to prevent being determined to stand up suddenly. Thereby, a vehicle speed command that realizes smoother vehicle operation can be generated.

  (5) Transient characteristics such as delay and overshoot according to the characteristics of the vehicle to be tested and the drive robot installed in the vehicle speed detection from the input of the vehicle speed command to the vehicle speed control device is there. In the present invention, in order to generate a vehicle speed command in consideration of this in advance, the extreme value of the evaluation function is searched using the output of the transient characteristic model simulating the transient characteristic as the vehicle speed value. As a result, a vehicle speed command can be generated so that the vehicle speed of the actual vehicle does not deviate from the allowable range.

  (6) According to the vehicle speed command generation method of the present invention, the same effect as the invention (1) of the vehicle speed command generation device described above can be obtained.

1 is a diagram illustrating an overall configuration of a vehicle test system to which a vehicle speed command generation device and a vehicle speed command generation method according to an embodiment of the present invention are applied. It is a figure which shows the relationship between a reference | standard vehicle speed command and a target vehicle speed command. It is a figure which shows the transient characteristic from target vehicle speed instruction | command to vehicle speed detection. It is a figure which shows the result of having input appropriate target vehicle speed command into the vehicle speed control apparatus, and actually performing vehicle speed control. It is the figure which expanded a part of upper stage of FIG.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram illustrating a configuration of a control system of a vehicle test system S to which a vehicle speed command generation device 1 and a vehicle speed command generation method according to the present embodiment are applied.

  The vehicle test system S includes a vehicle speed command generation device 1, a vehicle speed control device 2, and a control object 3. The control target 3 includes, for example, a chassis dynamometer that generates a running resistance imitating an actual road surface and a vehicle as a test target mounted on the chassis dynamometer. A drive robot for operating devices necessary for running the vehicle such as an accelerator pedal, a brake pedal, a shift lever, and an ignition switch in accordance with a command is mounted on the driver's seat of the vehicle. The vehicle speed command generation device 1 generates a target vehicle speed command corresponding to the vehicle speed to be realized at each time, and the vehicle speed control device 2 realizes the generated target vehicle speed command (in other words, an actual vehicle speed command). The drive robot is controlled so that the vehicle speed traces the target vehicle speed command.

  FIG. 1 shows only a portion related to determination of an accelerator opening command that is an input to an accelerator actuator among a plurality of actuators constituting the drive robot. The drive robot includes an actuator that operates a brake pedal, a shift lever, and the like in addition to an accelerator actuator that operates an accelerator pedal of a vehicle. However, illustration and detailed description of the configuration for determining input to these are omitted. . Hereinafter, configurations of the vehicle speed command generation device 1 and the vehicle speed control device 2 will be described in order.

  The vehicle speed command generation device 1 includes data relating to a reference vehicle speed command that is predetermined according to a standard according to the test content, and a vehicle speed allowable range (hereinafter referred to as “tolerance”) that is set in advance with respect to the reference vehicle speed command. And the target vehicle speed command is generated using them. Here, the “vehicle speed command” is a set of data in which a waveform of a target vehicle speed, that is, a plurality of times and vehicle speed values to be realized at each time are associated with each other.

  FIG. 2 is a diagram illustrating the relationship between the reference vehicle speed command and the target vehicle speed command. In FIG. 2, the thick solid line is the reference vehicle speed command (vref), and the thick broken line is an example of the target vehicle speed command (vcmd) generated by the vehicle speed command generation device with the reference vehicle speed command as an input.

  As described above, the reference vehicle speed command is determined by a standard or the like, but tolerance is set for the reference vehicle speed command in consideration of various errors. This tolerance is also determined by standards. As indicated by a broken line frame in FIG. 2, the tolerance of the tolerance is not only a speed shift at each time (a shift in the vertical direction in FIG. 2) but also a time shift. According to one standard defined in Japan, a speed deviation of ± 2 [km / h] is allowed, and a time deviation of ± 1 [s] is allowed. Thus, since the tolerance for the reference vehicle speed command allows both a speed deviation and a time deviation, the allowable speed upper limit (Tupper) and the allowable speed lower limit (Tlower) at each time are indicated by a one-dot chain line in FIG. It becomes a tolerance envelope as shown.

  The vehicle speed command generation device 1 includes a vehicle speed command generation unit 11 and an extreme value search unit 12, and by these functions, an allowable speed upper limit determined by the tolerance and a smooth mode operation closer to a person are realized. A new target vehicle speed command is generated within the allowable lower limit, and this is used as a command value for the vehicle speed control device 2. In order to realize this, the vehicle speed command generation device 1 uses nonlinear programming as described below.

The vehicle speed command generation unit 11 follows the difference equation as shown in the following formula (1), from the start time t = 0 to the end time t = tend (vcmd (0), vcmd (dt), vcmd (2dt) , ..., vcmd (tend)). Here, in the following formula (1), “dt” indicates a time interval of the generated vehicle speed command. “Dt” is, for example, 1 [s], but is not limited thereto. “A (t)” is the acceleration of the vehicle at time t. The following equation (1) means that if the acceleration a (t) at each time is determined, the vehicle speed command vcmd (t) at each time is determined by integrating the acceleration a (t). The vehicle speed command generation unit 11 generates a target vehicle speed command vcmd by integrating the value of acceleration a determined by a method described later at each time step dt.

Next, a procedure for determining the value of acceleration a (t) for each time step dt will be described. The extreme value search unit 12 defines an evaluation function J (t) including at least a power term W ² (t) proportional to the square of the acceleration a of the vehicle. Here, for example, any one of the following three types is preferably used for the power factor W ² (t). In the following formula, “M” is a vehicle weight and is a constant independent of time. “V (t)” is the speed of the vehicle at time t, and a value calculated using a predetermined algorithm is used. More specifically, for example, a value calculated by accumulating the value of acceleration a at each time in the same manner as the above equation (1) (for example, see Example 1 described later) or a predetermined vehicle model. A value obtained by inputting the target vehicle speed command vcmd (t) (for example, see Example 2 described later) or the like is used. Since the vehicle weight M is a constant, the target vehicle speed command vcmd finally obtained is almost the same between the case where the equation (2-1) is used and the case where the equation (2-2) is used. Below, although the case where the formula (2-1) with the most clear physical significance is used will be described, the present invention is not limited to this. Formula (2-2), Formula (2-3), or other definitions may be adopted as the power term W ² (t).

Next, the extreme value search unit 12 keeps the value of the vehicle speed v (t) within a permissible range determined by the permissible speed upper limit Tupper (t) and the permissible speed lower limit Tlower (t) at each time step dt (hereinafter referred to as the following). The acceleration a (t) is determined so that the evaluation function J (t) is minimized. Here, the constraint condition is expressed by the following equation (3). The vehicle speed command generation device searches for a minimum value of the evaluation function J (t) under a constraint condition by using a known nonlinear programming algorithm such as a steepest descent method or a conjugate gradient method.

  The vehicle speed command generation device 1 searches for the extreme value of the evaluation function J (t) as described above under appropriate initial conditions (vcmd (0), a (0), v (0)), and formula (1) The target vehicle speed command vcmd (t) between time t = 0 and tend is generated by alternately executing the generation of the target vehicle speed command vcmd (t) based on the time step dt. The specific procedure for generating the target vehicle speed command while imposing the constraint condition on the vehicle speed v (t) as described above will be described later in the first and second embodiments.

  Next, the configuration of the vehicle speed control device 2 will be described. For example, the vehicle speed control device 2 performs follow-up control of the target vehicle speed command by a control method in which feedforward control using a driving force characteristic map and PI control are combined as shown in FIG. Hereinafter, a specific configuration of the vehicle speed control device 2 will be described.

  The driving force characteristic map calculation unit 21 has a driving force characteristic map (not shown) in which predetermined inputs (target vehicle speed command and target driving force) and the opening degree of the accelerator pedal of the vehicle are associated. As this driving force characteristic map, a map prepared by conducting an experiment in advance for a vehicle to be tested is used. When the target vehicle speed command generated as described above and the target driving force determined by a process (not shown) are input, the driving force characteristic map calculation unit 21 searches the above-described driving force characteristic map, The accelerator opening corresponding to the input is determined.

  The vehicle speed feedback calculation unit 22 includes a vehicle sensitivity calculation unit 23, a proportional calculation unit 24, an integration calculation unit 25, and an addition unit 26. The vehicle sensitivity calculation unit 23 calculates the reciprocal of the vehicle sensitivity (drive force change / accelerator opening change) using the same driving force characteristic map as the calculation unit 21 has. The proportional calculation unit 24 multiplies the vehicle speed deviation (target vehicle speed command-actual vehicle speed) by a proportional gain that is varied according to vehicle sensitivity. The integral calculation unit 25 integrates the output of the proportional calculation unit 24. The adder 26 adds the output of the proportional calculator 24 and the output of the integral calculator 25.

  The output of the driving force characteristic map calculation unit 21 and the output of the vehicle speed feedback calculation unit 22 as described above are added by the addition unit 27 and input to the control target 3 as an accelerator opening degree command with respect to the opening degree of the accelerator pedal. The vehicle and chassis dynamometer system that is the control target 3 are divided into a vehicle drive system 31, an adder 32, and a vehicle inertia system 33. When the accelerator opening degree command is input, the vehicle drive system 31 generates a driving force corresponding to the accelerator opening degree command. The vehicle inertia system 33 receives a vehicle acceleration force obtained by subtracting a running resistance generated by the chassis dynamometer system from the drive force generated by the vehicle drive system 31. The vehicle inertia system 33 generates a vehicle speed according to the input of the acceleration force of the vehicle.

  The specific configuration of the vehicle speed control device 2 has been described above, but the present invention is not limited to this. The vehicle speed control device 2 may be any device as long as it has a function of following the target vehicle speed command.

Hereinafter, a first embodiment of the vehicle speed command generation device will be described. As described above, the extreme value search unit searches for the minimum value of the evaluation function J (t) under the constraint condition expressed by Expression (3). In the present embodiment, a case where a so-called barrier method (or interior point penalty method) is applied as a method for searching for the minimum value of the evaluation function J (t) under such constraint conditions will be described. In the barrier method, the so-called barrier function terms B (t) and Best (t) are added to the evaluation function J (t), as shown in the following equation (4), so that Replace with an unconditional extremum search problem.

  The first term on the right side of equation (4) is the power term expressed by equation (2). In the present embodiment, the value obtained by integrating the acceleration a (t) at every time step dt is used as the velocity v (t) in the equation (2), as in the equation (1).

The second term on the right side of Equation (4) is a velocity barrier function term for realizing the constraint condition of Equation (3). The velocity barrier function term is substantially zero when the value of the velocity v (t) is within the allowable range (Tlower (t) to Tupper (t)), and the velocity v (t) is within the allowable range and within the allowable velocity upper limit Tupper ( It preferably has a characteristic that diverges as it approaches the allowable speed lower limit Tlower (t). By adding the velocity barrier function term B (t) having such characteristics to the evaluation function, the extreme value of the evaluation function J (t) that satisfies the constraint condition can be obtained without determining whether the constraint condition is satisfied separately. Can be evaluated. More specifically, it is expressed by the following formula (5). In the following formula (5), “r” is a weighting factor that determines the influence degree of the barrier function, and is arbitrary.

The third term on the right side of Equation (4) is a look-ahead barrier function term that is added to prevent the finally calculated target vehicle speed command vcmd (t) from rapidly rising. More specifically, the look-ahead barrier function term is a barrier function term for realizing a constraint imposed on a predetermined predicted speed vest (t). Here, the predicted speed vest (t) corresponds to a predicted value of speed after a predetermined look-ahead time dt × n (“n” is an integer equal to or greater than 1, for example, 1) from the current time t. More specifically, for example, as shown in the following formula (6), a value calculated by integrating the current acceleration a (t) over the look-ahead time is used.

The look-ahead barrier function term is almost zero when the value of the predicted speed vest (t) is within the allowable range after the look-ahead time (Tlower (t + ndt) to Tupper (t + ndt)), and the predicted speed vest (t ) Diverges from the allowable range after the look-ahead time as it approaches the allowable speed upper limit Tupper (t + ndt) or the allowable speed lower limit Tlower (t + ndt). More specifically, it is expressed by the following formula (7). In the following equation (7), “r” is a weighting factor that determines the degree of influence of the barrier function, and is arbitrary.

  Next, a second embodiment of the vehicle speed command generation device will be described. The extreme value search unit of the vehicle speed command generation device of the present embodiment is different from the first embodiment in the method of calculating the vehicle speed v (t) used when calculating the evaluation function J (t).

  As shown in FIG. 3, the vehicle speed detection of the actual vehicle from the input of the target vehicle speed command to the vehicle speed control device is performed, such as delay or overshoot according to the characteristics of the vehicle to be tested and the drive robot mounted on the vehicle. There are transient characteristics. The extreme value search unit of the present embodiment defines a transient characteristic model simulating the transient characteristic from the target vehicle speed command to the vehicle speed detection by the transfer function G (s). Then, the extreme value search unit uses the output obtained by inputting the target vehicle speed command vcmd obtained for each time step dt according to the expression (1) into the transfer function G as the value of the vehicle speed v, using the expression (2 ) To (7), the extreme value of the evaluation function J is searched.

Here, for the transfer function G (s), for example, a transfer function of a second-order lag system as defined by the following equation (8) is used. In the following formula (8), “s” is a Laplace operator, “ζ” is a damping coefficient, “ωn” is a natural angular frequency, “K” is a gain constant, and “L” is a waste. 3, the vehicle speed output of the transfer function G (s) with the target vehicle speed command as an input is shown by a dark solid line, and the vehicle speed command shifts from a certain slope to a steady state as shown in FIG. It was verified that it was reproduced with high accuracy in the section.

Note that the transfer function G (s) of the transient characteristic model may use not only a second-order lag system as shown in Expression (8) but also a first-order lag system transfer function as shown in Expression (9) below. . In the following equation (9), “T” is a time constant, “K” is a gain constant, and “L” is a dead time.

Next, effects of the present invention will be described with reference to FIGS.
FIG. 4 is a diagram showing a result of actually performing vehicle speed control by inputting an appropriate target vehicle speed command to the vehicle speed control device. The upper part of FIG. 4 shows the time change of the vehicle speed, the middle part shows the time change of the accelerator opening, and the lower part shows the time change of the brake opening. In FIG. 4, the thinnest solid line indicates the result when the reference vehicle speed command is directly input to the vehicle speed control device as the target vehicle speed command (hereinafter referred to as “Comparative Example 1”). The second thinnest broken line shows the result when the method described in Japanese Patent Application Laid-Open No. 2009-8517, that is, the reference vehicle speed command subjected to moving average processing is input to the vehicle speed control device as the target vehicle speed command (hereinafter, "Comparative example 2"). More specifically, the darkest solid line shows the result when the target vehicle speed command generated using the vehicle speed command generation device of the second embodiment is input to the vehicle speed control device (hereinafter referred to as “the present invention”). In addition, the thin broken lines in the upper part of FIG.
FIG. 5 is an enlarged view of a part of the upper part of FIG.

  As shown at time 25 to 27 [s] in FIG. 5, in Comparative Example 1 in which the reference vehicle speed command is input as it is, the vehicle speed suddenly rises. In the present invention, such a sudden rise in vehicle speed is eliminated. .

  As shown at times 41 to 43 [s] in FIG. 5, in Comparative Example 1 and Comparative Example 2, the place where the vehicle speed should become flat is slightly overshooted. This is thought to be due to the accelerator pedal being depressed too much. On the other hand, in the present invention, such overshoot is reliably eliminated.

  As shown at time 49 [s] in FIG. 5, in the first comparative example, the brake is applied too much to prevent the vehicle speed from deviating from the tolerance, and the vehicle speed is greatly reduced. On the other hand, in the present invention, it is possible to prevent the brake from being operated at an unnecessary timing.

  Next, the brake operation will be verified with reference to the lower part of FIG. As shown in the lower part of FIG. 4, it can be confirmed that the brake is frequently depressed at a timing unnecessary in Comparative Example 1. Further, when comparing the present invention with Comparative Example 2, the timing at which the brake is depressed tends to be slightly faster in Comparative Example 2. Moreover, as shown by the broken line in the middle part of FIG. 4, it can be confirmed that the brake is depressed more in Comparative Example 2 in some places. Therefore, it has been verified that by using the target vehicle speed command generated by the present invention, a natural braking operation without flapping can be realized by the drive robot.

  Next, the accelerator operation will be verified with reference to the middle part of FIG. As shown in the middle part of FIG. 4, in the comparative example 1, the accelerator on / off operation is clearly intense. That is, in Comparative Example 1, there are many places where the accelerator is depressed or released at unnecessary timing. Further, when the present invention is compared with Comparative Example 2, the timing at which the accelerator is depressed or released is similar. However, the change in the accelerator opening is larger in Comparative Example 2 than in the present invention at some points indicated by broken lines. Therefore, it has been verified that by using the target vehicle speed command generated by the present invention, a natural accelerator operation without flapping can be realized by the drive robot.

DESCRIPTION OF SYMBOLS 1 ... Vehicle speed command production | generation apparatus 11 ... Vehicle speed command production | generation part (vehicle speed production | generation means)
12: Extreme value search unit (extreme value search means)

Claims (6)

When a vehicle speed command corresponding to the speed of the vehicle to be realized is input, a vehicle speed command generation device that generates a vehicle speed command used in the vehicle speed control device for a vehicle speed control device of a drive robot that operates the vehicle according to the vehicle speed command Because
Extreme value search means for determining an acceleration value such that the value of the evaluation function including a term proportional to the square of the acceleration of the vehicle becomes an extreme value;
Vehicle speed command generating means for generating a vehicle speed command using the determined acceleration value,
The extreme value searching means determines an acceleration value so that the speed value of the vehicle is within an allowable range determined for a predetermined reference vehicle speed command and the value of the evaluation function is an extreme value. A vehicle speed command generating device.   The vehicle speed command generation device according to claim 1, wherein the evaluation function includes a power term proportional to a product of the square of the acceleration and the square of the speed.   The evaluation function further includes a speed barrier function term that increases when the speed value approaches the speed upper limit value from within the allowable range and increases when the speed value approaches the speed lower limit value from within the allowable range. The vehicle speed command generation device according to claim 1 or 2. The extreme value search means calculates a predicted value of the speed after a predetermined look-ahead time based on the current value of the acceleration,
The evaluation function is increased when the predicted value of the speed approaches the upper speed limit at that time from within the allowable range after the pre-reading time and the predicted value of the speed is within the allowable range after the pre-reading time and the lower speed limit at that time. The vehicle speed command generation device according to any one of claims 1 to 3, further comprising a look-ahead barrier function term that increases as the value approaches.   The extreme value searching means uses a transient characteristic model simulating a transient characteristic from the vehicle speed command to the drive robot to the speed detection of the vehicle, and uses the vehicle speed command generated by the vehicle speed command generating means as the transient characteristic model. 5. The vehicle speed command generation device according to claim 1, wherein an extreme value of the evaluation function is searched by using an output obtained by input as a speed value of the vehicle. Vehicle speed command generation method for generating a vehicle speed command used in a vehicle speed control device for a vehicle speed control device of a drive robot that operates a vehicle according to the vehicle speed command when a vehicle speed command corresponding to the speed of the vehicle to be realized is input Because
An extreme value search step for determining an acceleration value such that the value of the evaluation function including a term proportional to the square of the acceleration of the vehicle becomes an extreme value;
A vehicle speed command generating step for generating a vehicle speed command using the determined acceleration value, and
In the extreme value search step,
Vehicle speed command generation characterized in that an acceleration value is determined so that a value of the vehicle speed falls within an allowable range determined with respect to a predetermined reference vehicle speed command and the value of the evaluation function becomes an extreme value. Method.